Alkyl, Hydride, and Hydroxide

ALKYL, HYDRIDE, AND HYDROXIDE DERIVATIVES OF THE s- AND p-BLOCK ELEMENTS SUPPORTED BY POLY(PYRAZOLYL)BORATO LIGATION MODELS FOR CARBONIC ANHYDRASE, RECEPTORS FOR ANIONS, AND THE STUDY OF CONTROLLED CRYSTALLOGRAPHIC DISORDER... 

Alkyl, Hydride, and Hydroxide Derivatives in the s- and p-Block Elements Supported by Poly(pyrazolyl)borato Ligation Models for Carbonic Anhydrase, Receptors for Anions, and the Study of Controlled Crystallographic Disorder Gerard Parkin... 

Alkyl bromides and especially alkyl iodides are reduced faster than chlorides. Catalytic hydrogenation was accomplished in good yields using Raney nickel in the presence of potassium hydroxide [63] Procedure 5, p. 205). More frequently, bromides and iodides are reduced by hydrides [505] and complex hydrides in good to excellent yields [501, 504]. Most powerful are lithium triethylborohydride and lithium aluminum hydride [506]. Sodium borohydride reacts much more slowly. Since the complex hydrides are believed to react by an S 2 mechanism [505, 511], it is not surprising that secondary bromides and iodides react more slowly than the primary ones [506]. The reagent prepared from trimethoxylithium aluminum deuteride and cuprous iodide... 

The addition of a benzene solution of an alkyl chlorocarbonate to an aqueous solution of sodium tclluride (prepared from tellurium and Rongalite in an aqueous solution of sodium hydroxide) containing tetrabutylammonium bromide as a phase-transfer agent produced the bis[alkoxycarbonyl] tellurium at 20 . The reactions can also be carried out in dimethylformamide with sodium telluride obtained from sodium hydride and tellurium in dimethylformamide4... 

Carbon dioxide readily undergoes insertion reactions probably via initial C02 complexing, with metal alkoxides, hydroxides, oxides, dialkylamides, and metal hydrides and alkyls 103... 

The insertion of carbon dioxide probably involves C02 complexes as intermediates and is known for alkyls, hydrides,204 dialkylamides, dialkylphosphides, hydroxides,205... 

Water-soluble polyether tin hydride and the bis(2-cardoxyethyl)tin hydroxide allowed reductions and cyclizations to be carried out in water with easy separation from organic soluble products. The latter tin reagent is generated in situ and has not been characterized, but may be a multiplicity of tin oxides and hydroxides. It is soluble in dilute alkali and catalyzes the reduction of alkyl and aryl bromides in the presence of NaBH4 and the water-soluble initiator 4,4 -azobis(4-cyanovaleric acid) (AVCA). 

Fig. 7. TPD traces from alkyl iodides adsorbed on oxygen- (left) and hydroxide- (right) precovered Ni(lOO) surfaces. The bottom traces correspond to the formation of acetaldehyde from ethyl iodide, while those on top display the desorption of acetone from 2-propyl iodide conversion. The enhancing power of OH surface groups towards partial oxidation pathways is indicated by two observations from these data (1) the yield for acetone increases to the point of resembling that seen with 2-propanol and (2) some acetaldehyde is detected as well. It is at the present time unclear if the OH groups favor the formation of alkoxide intermediates or the subsequent P-hydride elimination step.

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